As a young boy, Joseph and his family fled the Soviet Union with the help of a man known as The General.
Growing up, his father would berate him for speaking Italian in their Russian household, and would beat the boy with a hammer when punishing him. In school he would lie and say he was Italian, only for a bully named Rico to reveal his lie and steal the hat he wore showing the ugly scars on his head from frequent hammer blows.
Rico and his girlfriend would be the kills Hammerhead needed to join the mob. Hammerhead convinced the mob that he was Italian, which was necessary since they did not take 'inferior stock'. He eventually killed his father with a much bigger hammer than his father had ever used on him.
Hammerhead began his career as a junior hit-man, working for the Maggia. When his head was shattered in a brawl, Jonas Harrow discovered him in an alley, and operated on him - replacing his broken skull with one made of steel. Hammerhead clearly had mental and emotional problems prior to his injury, and they were exacerbated by the trauma.
Upon awakening, Hammerhead became fixated on a 1920's movie poster which had been the last thing he saw before the brawl. He adopted the identity of the mobster "Hammerhead", favoring 20's clothing, weaponry, speech patterns and behavior of the criminals of that time. He claimed to no longer remember his real name.
Hammerhead was also involved with Doc Ock when he attempted to woo Peter Parker's Aunt May. He was apparently killed in a nuclear explosion and began haunting Octavius as a ghost. He was brought back to life with a device that Octavius had built to dissipate the ghost. He kidnapped Aunt May, but was defeated by a temporary alliance of Octopus and Spider-Man.
During the events of the Civil War, Hammerhead used the vacuum left by the incarceration of the Kingpin to gain a greater foothold in the ranks of organized crime, attempting to organize an army of costumed villains (consisting of but not limited to the Ani-Men V, Answer I, Aura, Bloodshed, Clown, Commanda, Cyclone III, Discus, Electro, Great Gambonnos, Kangaroo II, Man Mountain Marko, Mauler, Mindblast, Override, Ringmaster, Slyde, Spot, Squid, Stiletto, Trapster, and Will O' The Wisp) to enforce his new criminal empire. The Kingpin manipulated various hero factions, most notably S.H.I.E.L.D. and Iron Man into breaking up Hammerhead's first convening of his army. During the conflict, Hammerhead was shot numerous times by Fisk's agent Underworld, who later confronted Hammerhead while he lay in a prison hospital. Underworld then shot Hammerhead at point-blank range with adamantium bullets.
The bullets, while not penetrating his skull, did cause severe trauma to his brain, resulting in him needing surgery, but the hospital he was brought to was unable to treat him. In mid-surgery, men working for Mister Negative came in, killed the hospital staff, and took Hammerhead away. Mister Negative then had his surgeon, Doctor Tramma, revive Hammerhead, and offered to transplant his brain into a new robotic adamantium skeleton, to which Hammerhead agreed.
Hammerhead's first task as a member of Mister Negative's organization was to consolidate all of the Bronx gangs to go up against the Maggia. He happened to attack new acquaintances of Spider-Man and fought with him. Although his new strength and body allowed him to initially beat Spider-Man and dislocate his jaw, he was later defeated when Spider-Man realized he was "top heavy" and was able to take out his legs.
Black Cat's Gang
Hammerhead and the rest of his henchmen later allied themselves with the Black Cat to take down the new Spider-Man, which marked the beginning of a formal partnership. Hammerhead became Black Cat's muscle and second in command. When the returned Diamondback set his sights on becoming the next Kingpin of New York, he shot and critically injured the Black Cat. He then confronted Hammerhead at his pub. One of Joseph's own men, paid by Diamondback, shot him in the back of the head with a special high-caliber gun, killing him. However, Hammerhead's death was short lived. While his body was on the morgue, it was resurrected with a Norn Stone by the The Hood, another player who was making a move for the position of Kingpin of New York.
When the Owl declared himself the new Kingpin of New York after Wilson Fisk dissolved his crime empire, he declared war against the Libris Family. Hammerhead was recruited by Izzy Libris to take down the Owl. However, Libris became increasingly disproving of Hammerhead's avarice. She managed to free up some of her reserve funds and bought out Hammerhead's men, inciting a coup of Joseph's operations and shooting him in the head. It was later revealed that Hammerhead had survived.
Cybernetic Enhancements: After Hammerhead was shot, he needed to undergo intensive reconstructive surgery. Mister Negative offered to replace his entire upper skeleton with a brand new cybernetic one made of adamantium. Hammerhead accepted the offer, and thus became far stronger than ever before.
- Superhuman Strength
- Superhuman Durability
Criminal organization, Experienced hand-to-hand combatant. 
Mentally unstable. His exoskeleton only covers the upper parts of his body since hits to the lower back still hurt and his hip was still able to be dislocated.
Tommy guns, machine guns, other heavy weaponry - sometimes uses "stun" bullets.
- Hammerhead was one of the characters featured in Series A of the Marvel Value Stamps issued in the 1970's.
- Joseph is against hitting women and children.
- 153 appearance(s) of Hammerhead (Joseph) (Earth-616)
- 28 minor appearance(s) of Hammerhead (Joseph) (Earth-616)
- 29 mentions of Hammerhead (Joseph) (Earth-616)
- 80 image(s) of Hammerhead (Joseph) (Earth-616)
- 4 quotation(s) by or about Hammerhead (Joseph) (Earth-616)